fix: Controlnet Prepreocessed Image Save Icon Missing (#4375)

## What type of PR is this? (check all applicable)

- [ ] Refactor
- [ ] Feature
- [ ] Bug Fix
- [ ] Optimization
- [ ] Documentation Update
- [ ] Community Node Submission


## Have you discussed this change with the InvokeAI team?
- [ ] Yes
- [ ] No, because:

      
## Have you updated all relevant documentation?
- [ ] Yes
- [ ] No


## Description


## Related Tickets & Documents

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## QA Instructions, Screenshots, Recordings

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## Added/updated tests?

- [ ] Yes
- [ ] No : _please replace this line with details on why tests
      have not been included_

## [optional] Are there any post deployment tasks we need to perform?

invokeai/frontend/web/src/features/controlNet/components/ControlNetImagePreview.tsx

@@ -180,11 +180,19 @@ const ControlNetImagePreview = ({ isSmall, controlNet }: Props) => {
           isUploadDisabled={true}
           isDropDisabled={!isEnabled}
         >
+          <>
             <IAIDndImageIcon
               onClick={handleResetControlImage}
               icon={controlImage ? <FaUndo /> : undefined}
               tooltip="Reset Control Image"
             />
+            <IAIDndImageIcon
+              onClick={handleSaveControlImage}
+              icon={controlImage ? <FaSave size={16} /> : undefined}
+              tooltip="Save Control Image"
+              styleOverrides={{ marginTop: 6 }}
+            />
+          </>
         </IAIDndImage>
       </Box>
       {pendingControlImages.includes(controlNetId) && (